The present invention relates to microfluidic systems, including flexible microfluidic systems and valves and pumps for microfluidic systems. The present invention also relates to a method of making a microfluidic system suitable for use with a polymeric material.
Microfluidic systems are flow systems miniaturized to dimensions as small as a few, micrometers (xcexcm). Such systems present challenges in both their design and manufacture. For example, at the level of miniaturization of typical microfluidic systems, normal fluid flow principles may be less significant than surface tension.
Recent developments in microfluidic systems have been motivated in large part by the possibility of fabricating compact, integrated devices for analytical functions such as genomic analysis, diagnosis and sensing.
According to one embodiment of the present invention, a microfluidic system is provided including a fluid path, an inlet and an outlet to the fluid path, and a first closing member disposed along the fluid path between the inlet and the outlet. In this embodiment of the invention, the fluid path has a cross-sectional dimension of less than about 500 xcexcm.
According to another embodiment of the present invention, a valve having an open position and a closed position is provided. The valve includes a fluid path and an inlet and an outlet to the fluid path. A flexible diaphragm having an opening is disposed along the fluid path between the inlet and the outlet to the fluid path. In this embodiment of the invention, a seat is constructed and arranged such that, when the valve is in the closed position, the seat obstructs the opening and supports the flexible diaphragm around at least the periphery of the opening.
According to another embodiment of the present invention, a microfluidic pump is provided including a fluid path, an inlet to the fluid path and an outlet to the fluid path. A first closing member and a second closing member are each disposed along the fluid path between the inlet and the outlet, and a reservoir having a variable volume is disposed along the fluid path between the first closing member and the second closing member. In this embodiment of the invention, the fluid path has a cross-sectional dimension of less than about 500 xcexcm.
According to another embodiment of the present invention, a microfluidic system is provided including a flexible support, a flexible material connected to the flexible support, and a fluid path within the flexible material having a cross-sectional dimension of less than about 500 xcexcm.
According to a further embodiment of the present invention, a method for making a microfluidic system is provided. The method includes providing a master corresponding to the microfluidic system, forming the microfluidic system on the master, connecting a support to the microfluidic system and removing the microfluidic system from the master.
According to another embodiment of the present invention, a method for opening a microfluidic valve is provided. The method includes providing a microfluidic valve and a flow of a fluid through a fluid path. The microfluidic valve includes the fluid path, an inlet and an outlet to the fluid path, and a first closing member disposed along the fluid path between the inlet and the outlet. The method further includes deflecting the closing member with the flow from a closed position to an open position without the closing member sliding against any portion of the microfluidic valve. In this embodiment of the invention, the fluid path has a cross-sectional dimension of less than about 500 xcexcm.
According to another embodiment of the present invention, a method for manipulating a flow of a fluid in a microfluidic system is provided. The method includes providing a fluid path having a cross-sectional dimension of less that about 500 xcexcm, initiating the flow of the fluid through the fluid path in a first direction, and inhibiting the flow of the fluid through the fluid path in a second direction.
According to another embodiment of the present invention, a microfluidic system includes a first fluid path, a second fluid path, and a first closing member comprised of a voltage degradable material and disposed between the first and second fluid paths. In this embodiment, one of the first and second fluid paths has a cross-sectional dimension of less than about 500 xcexcm.
According to another embodiment of the present invention, a microfluidic system includes a first fluid path, a second fluid path, and a first closing member comprised of a voltage degradable material and disposed between the first and second fluid paths. In this embodiment, the first closing member has a thickness of less than about 500 xcexcm.
According to another embodiment of the present invention, a microfluidic device includes a substantially sealed fluid reservoir, a fluid positioned within the fluid reservoir, a fluid path separated from the fluid reservoir by a closing member, a first electrode connected to the fluid reservoir, and a second electrode connected to the fluid path.
According to another embodiment of the present invention, a method of manipulating fluid flow in a fluidic system includes creating a voltage difference between a first fluid path and a second fluid path separated by a closing member, the voltage being sufficient to form an opening in the closing member. The method further includes allowing a fluid to flow between the first and second fluid paths.
According to another embodiment of the present invention, a method of testing includes introducing a test fluid into a test reservoir. The method also includes creating a voltage difference between the test reservoir and a reagent reservoir containing a reagent and separated from the test reservoir by a closing member, the voltage difference being sufficient to make an opening in the closing member. The method further includes allowing at least one of the test fluid and the reagent to flow between the test reservoir and the reagent reservoir.
According to another embodiment of the present invention, a method of making an opening in a fluidic system includes creating a voltage difference between a first fluid path and a second fluid path separated from the first fluid path by a closing member sufficient to make an opening in the closing member.
Other advantages, novel features, and objects of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings, some of which are schematic and which are not intended to be drawn to scale. In the figures, each identical or nearly identical component that is illustrated in various figures is represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the invention shown where illustration is not necessary to allow those of ordinary skill in the art to understand the invention.